Not Applicable.
The present embodiments relate generally to data communications security and, more particularly, to a layered data protection system which provides secured communications over the IEEE 1394-1995 High Performance Serial Bus (hereinafter, xe2x80x9cthe 1394 busxe2x80x9d).
With the advent of the ""1394 Bus, it is anticipated and indeed an exciting expectation that much larger and faster data capabilities will soon be implemented in numerous computer-controlled applications Such applications currently contemplate various consumer implementations, likely supporting various data formats, including DVD (originally identified as xe2x80x9cDigital Video Discxe2x80x9d but now more often called xe2x80x9cDigital Versatile Discxe2x80x9d because it can be used to store computer data as well as video), digital VCR (xe2x80x9cD-VCRxe2x80x9d), digital satellite system, digital television (DTV), and possibly others. With these capabilities, however, there arises a heightened concern on behalf of the creators and owners of the data to protect it as it passes along the system on the 1394 bus. The present embodiments are directed to such issues.
A key factor in achieving an effective implementation of any or all of the components of the present embodiments as well as other data protection systems is the elimination of data in-the-clear on any accessible interfaces. The value of having robustly encrypted data on a digital interface such as the 1394 interface will be completely negated if the unencrypted form of that data is also available at some other accessible location. This leads to two conclusions which may be implemented using the preferred embodiments discussed later: (1) The data should be encrypted before leaving the original source equipment, such as internally in a DVD drive or the Network Interface Module in a set top box; and (2) The data should stay encrypted until it is received within the destination equipment, such as a TV or monitor.
These goals are relatively easy to achieve for traditional closed-box, non-modifiable consumer electronic equipment, but are significantly more difficult to achieve for a personal computer (PC). In this latter case the PC equipment is designed to be easily opened and modified with changeable cards or modules having standardized interfaces such as the ISA and PCI busses, or the advanced graphics port. Allowing data in-the-clear to travel over any of these busses or interfaces leaves a tempting opportunity for black market add-ons which may tap into the data stream for recording and subsequent playback and reproduction.
In view of the above, there arises a need to address the increase in protection of data to be communicated, or while being communicated, over the ""1394 bus, and this need should be balanced in terms of other resource issues such as the cost and complexity of the protection structure and methods, as well as the likelihood of a wrongdoer overcoming the protection provided by such structure and methods.
In one embodiment, there is a method of communicating from a transmitter to a receiver over a communications medium. For the transmitter, the method includes the step of formatting data into a data stream to be communicated across the communications medium. This data stream comprises a plurality of headers. Moreover, for each of the plurality of headers, the method performs two steps. First, the method modifies information encoded by the header by performing a bitwise logical operation between selected bits of the header with a predetermined bit pattern. Second, the method transmits the plurality of headers on to the communications medium. For the receiver, the method includes the step of receiving the plurality of headers from the communications medium. Additionally, for each of the received headers, the receiver recovers the information encoded by the header.
In another embodiment, there is provided an information package medium. The package medium comprises means for storing a plurality of data quantities. Each of the plurality of data quantities comprises a set of bits. The package medium further comprises a plurality of machine-readable scramble codes, and each of the plurality of machine-readable scramble codes corresponds to one of the plurality of data quantities and indicates a manner of descrambling the corresponding one of the plurality of data quantities.
Other circuits, systems, and methods are also disclosed and claimed.